The thickness of the web of a mild steel plate girder is less than d/200. If only one horizontal stiffener is used, it is placed at
The neutral axis of the section
2/3rd of the depth of the neutral axis from the compression flange
2/5th of the depth of the neutral axis from the compression flange
2/5th of the height of the neutral axis from tension flange
Correct Answer :
C. 2/5th of the depth of the neutral axis from the compression flange
Related Questions
Study the following statements. (i) Top lateral bracing prevents the sides-way buckling of the chord. (ii) Sway bracing keeps the rectangular shape of the bridge crosssection. (iii) Sway bracing transfers the load from top of end posts to bearings. The correct answer is
Only (i)
Both (i) and (ii)
Both (i) and (iii)
All (i), (ii) and (iii)
Intermediate vertical stiffeners in a plate girder need be provided if the depth of web exceeds
50 t
85 t
200 t
250 t Where t is thickness of web
A second horizontal stiffener is always placed at the neutral axis of the girder if the thickness of the web is less than
d/250 for structural steel
d/225 for high tensile steel
Both (c) and (b)
Neither (a) nor (b)
The net area of round bars to resist the tension, is the area of cross section at
Mid-section
Root of the thread
Difference of (a) and (b)
None of these
The internal pressure coefficient on walls for buildings with large permeability is taken as
± 0.2
±0.5
± 0.7
0
Working shear stress on the gross area of a rivet as recommended by Indian Standards, is
785 kg/cm2
1025 kg/cm2
2360 kg/cm2
None of these
Lug angles
Are used to reduce the length of connection
Are unequal angles
Increases shear lag
All the above
In a built up beam actual bending compressive stress fbc is given by (when y1 is the distance of the edge of the beam from the neutral axis).
fbc = (M/Ixx) × y₁
fbc = (Ixx/M) × y₁
fbc = (Ixx/M) + y₁
fbc = (M/Ixx) + y₁
The moment of the couple set up in a section of a beam by the longitudinal compressive and tensile force, is known as
Bending moment
Moment of resistance
Flexural stress moment
None of these
If p and d are pitch and gross diameter of rivets, the efficiency (η) of the riveted joint, is given by
η = p/p - d
η = p/p + d
η = p - d/p
η = p + d/p
The equivalent axial load may be defined as the load which produces a stress equal to
Maximum stress produced by the eccentric load
Maximum stressed fibre
Bending stress
None of these
If R is the reaction on the bearing plate, the minimum moment of. inertia of the bearing stiffener provided at the support of a plate girder of overall depth D, the maximum thickness of the compression flange T, carrying total load W, is
(D²/250) × (R/W)
(D3T/250) × (R/W)
(DT/250) × (R/W)
(DT/250) × (W/R)
The effective length of a battened strut effectively held in position at both ends but not restrained in direction is taken as
1.8 L
L
1.1 L
1.5 L
IS : 800 - 1971 recommends that in a splice plate the number of rivets carrying calculated shear stress through a packing greater than 6 mm thick, is to be increased by 2.5% for every
1.00 mm thickness of packing
1.50 mm thickness of packing
2.0 mm thickness of packing
2.50 mm thickness of packing
According to the Unwin's formula, if t is thickness of the plate in mm, the nominal diameter of the rivet, is
d = 1.91 t
d = 1.91 t2
d = 1.91 √t
d = 1.91 t
A compression member consisting of angle sections may be a
Continuous member
Discontinuous single angle strut
Discontinuous double angle strut
All the above
A butt weld is specified by
Effective throat thickness
Plate thickness
Size of weld
Penetration thickness
The forces acting on the web splice of a plate girder are
Axial forces
Shear and axial forces
Shear and bending forces
Axial and bending forces
The size of a butt weld is specified by the effective throat thickness which in the case of incomplete penetration, is taken as
½ of the thickness of thicker part
¾ of the thickness of thicker part
¾ of the thickness of thinner part
7/8 of the thickness of thinner part
In a truss girder of a bridge, a diagonal consists of mild steel flat 4001.S.F. and carries a pull of 80 tonnes. If the gross-diameter of the rivet is 26 mm, the number of rivets required in the splice, is
6
7
8
9
The method of design of steel framework for greatest rigidity and economy in weight, is known as
Simply design
Semi-rigid design
Fully rigid design
None of these
The ratio of plastic section modulus to elastic section modulus
Is equal to 1
Is always less than 1
Is always greater than 1
Can be less than 1
An imaginary line along which rivets are placed, is known as
Rivet line
Back line
Gauge line
All the above
Effective length of a column effectively held in position and restrained in direction at both ends, is
L
0.67 L
0.85 L
1.5 L
The mechanism method and the statical method give
Lower and upper bounds respectively on the strength of structure
Upper and lower bounds respectively on the strength of structure
Lower bound on the strength of structure
Upper bound on the strength of structure
Bolts are most suitable to carry
Shear
Bending
Axial tension
Shear and bending
In double lacing, the thickness t of flat lacing is
t < 1/40 th length between inner end rivets
t < 1/50 th length between inner end rivets
t < 1/60 th length between inner end rivets
t < 1/70 th length between inner end rivets
Maximum pitch of rivets, used in steel stacks, is limited to
6 t
10 t
12 t
16 t Where t is thickness of thinner plate being connected
The beam outside a wall upto floor level above it, is known as
Rafter
Purlin
Spandrel beam
Lintel
The allowable shear stress in the web of mild steel beams decreases with
Decrease in h/t ratio
Increase in h/t ratio
Decrease in thickness
Increase in height Where 'h' is height and t is thickness